The number of endpoint devices in, or connected to, computing devices has recently increased dramatically. Endpoint devices may be used to control and measure parameters within a computing device such as fan speed, memory configuration and voltage settings. Unfortunately, as the number of functions controlled by these devices increases, so too does the associated security threat. For example, a malicious party may take over an internal bus and attempt to issue unauthorized commands to one or more of the endpoint devices, damaging, or possibly destroying, the computing device itself. In certain deployments, such as government and financial networks, for example, such threats may lead to costly damages, or worse. However, preventing a malicious party from issuing unauthorized commands over an internal bus can be difficult, particularly if the malicious party has gained control of one or more of endpoint devices that are connected to the bus.